| Abstract |
Present state of the control technique for converter-fed synchronous machines with machine-commutated inverter is the constant margine angle control. With this method, the motor and input reactive power is minimized. More than that, with additional .equipment, control of the input reactive power is possible. The manipulated variable is the extinction angle of the motor-side inverter. Adding a mains displacement meter and controller to the basic control system, a closed loop input reactive power control is achieved. Reactive power can thus be controlled over a certain range, limited by the system properties. This reactive power control lends itself particularly well to special applications, i.e. load torque varying with the square of the speed. It provides together with a low step switched reactive power compensator, a constant input reactive power. The concept, calculations and measurements of an industrial, microprocessor-controlled drive system of this kind are represented. |
